ArcGIS Pro – Page 2 – Master of Spatial Analysis

Monitoring Water Level Changes Using High Spatial and High Temporal Resolution Satellite Imagery

Author: Menglu Wang

Geovis Project Assignment @RyersonGeo, SA8905, Fall 2019

Introduction

The disappearing of the once world’s fourth largest lake, Aral Sea, was a shocking tragedy to the world, not only just the shrinkage of lake volume from 1,093.0 km3 in 1960 to 98.1 km3 in 2010 ( Gaybullaev et al., 2012), but also, the rate of shrinkage. Impacts on environment, local climate, citizen’s health, and agriculture are irreversible. This human made disaster could have been prevented in some degree if close monitoring of the lake was made and people are more educated about the importance of ecosystem. One efficient approach to monitor lake water level changes is the utilizing of satellite imagery .The spreading of free high spatial and high temporal resolution satellite imagery provides excellent opportunity to study water level changes through time. In this study, spatial resolution in 3 and 5 meters and temporal resolution as high as 3 days per visit PlanetScope Scene Satellite Imagery are obtained from Planet website. Iso-Cluster Unsupervised Classification in ArcGIS Desktop and Animation Timeline in ArcGIS Pro are used. Study area is set to Claireville Reservoir and 10 dates of imagery starting from April to late June are used to study water level changes.

Data Acquisition

To download the satellite imagery, a statement of research interest needed to be submitted to Planet Sales personal on their website (https://www.planet.com/). After getting access, go on typing in the study area and select a drawing tool to determine an area of interest. All available imagery will load up after setting a time range, cloud cover percentage, area coverage, and imagery source. To download a imagery, go select a imagery and click “ORDER ITEM” and items will be ready to download on the “Orders” tab when you click on your account profile. When downloading a item, noticing that there is a option to select between “Analytic”, “Visual”, and “Basic”. Always select “Analytic” if analysis will be made on the data. “Analytic” indicating geometric and radiometric calibration are already been made to imagery.

Methodology

ArcGIS desktop is used to implement classification and data conversion. Following after, ArcGIS Pro is used to create a animated time slide. Steps are list below:

After creating a file geodatabase and opening a map, drag imagery labeled letter ending with “SR” (surface reflectance) into the map .
Find or search “Mosaic To New Raster” and use it to merge multiple raster into one to get a full study area (if needed).
Create a new polygon feature class and use it to cut the imagery into much smaller dataset by using “Clip”. This will speed up processing of the software.
Grab “Image Classification” tool from Customize tab on top after selecting “Toolbars”.
On “Image Classification” toolbar, select desired raster layer and click on “Classification”. Choose Iso Cluster Unsupervised classification. Please see Figure 1. for classified result.
Identify classes that belong to water body. Search and use “Reclassify” tool to set a new value (for example: 1) for classes belong to water body, leave new value fields empty for all the rest of classes. Check “ Change missing values to NoData” and run the tool. You will get a new raster layer contain only 1 class: water body as result (Figure 2. and Figure 3.).
Use “Raster to Polygon” tool to convert resulted raster layer to polygons and clean up misclassified data by utilizing editor tool bar. After select “Start editing” from Editor drop down menu, select and delete unwanted polygons (noises).
Use resulted polygons to cut imagery in order to get a imagery contain water bodies only.
Do the above process for all the dates.
Open ArcGIS Pro and connect to the geodatabase that has been using in ArcGIS Desktop.
Search and use “Create Mosaic Dataset” tool to combine all water body raster into one dataset. Notes: Select “Build Raster Pyramids” and “Calculate Statistics” in Advanced Options.
After creating a mosaic dataset, find “Footprint” under the created layer and right click to open attribute table.
Add a new field, set data type as “text” and type in dates for these water body entries. Save edited table.
Right click on the layer and go to properties. Under time tab, select “each feature has a single time field” for “Layer Time”, select the time field that just has been created for “Time Field”, and specify the time format same as the time field format.
A new tab named “Time” will show up on first line of tabs in the software interface.
Click on the “Time” tab and specify “Span”. In my case, the highest temporal resolution for my dataset is 3 days, so I used 3 days as my “Span”.
Click the Run symbol in the “Play Back” section of tabs and one should see animated maps.
If editing each frame is needed, go to “Animation” tab on the top and select “Import” from tabs choose “Time Slider Step”. A series will be added to the bottom and waiting to be edited.
To export animated maps as videos, go to “Movie” in “Export” section of Animation tabs. Choose desired output format and resolution.

Figure 3. Reclassified satellite imagery

Conclusion

A set of high temporal and high spatial resolution imagery can effectively capture the water level changes for Claireville Reservoir. The time range is 10 dates from April to June, and as expected, water level changes as time pass by. This is possibly due to heavy rains and flood event which normally happens during summer time. Please see below for animated map .

Reference

Gaybullaev, B., Chen, S., & Gaybullaev, D. (2012). Changes in water volume of the Aral Sea after 1960. Applied Water Science, 2(4), 285–291. doi: 10.1007/s13201-012-0048-z

Visualizing Urban Land Use Growth in Greater Sào Paulo

By: Kevin Miudo

Geovis Project Assignment @RyersonGeo, SA8905, Fall 2018

https://www.youtube.com/watch?v=Il6nINBqNYw&feature=youtu.be

Introduction

In this online development blog for my created map animation, I intend to discuss the steps involved in producing my final geovisualization product, which can be viewed above in the embedded youtube link. It is my hope that you, the reader, learn something new about GIS technologies and can apply any of the knowledge contained within this blog towards your own projects. Prior to discussing the technical aspects of the map animations development, I would like to provide some context behind the creation of my map animation.

Cities within developing nations are experiencing urban growth at a rapid rate. Both population and sprawl are increasing at unpredictable rates, with consequences for environmental health and sustainability. In order to explore this topic, I have chosen to create a time series map animation visualizing the growth of urban land use in a developing city within the Global South. The City which I have chosen is Sào Paulo, Brazil. Sào Paulo has been undergoing rapid urban growth over the last 20 years. This increase in population and urban sprawl has significant consequences to climate change, and such it is important to understand the spatial trend of growth in developing cities that do not yet have the same level of control and policies in regards to environmental sustainability and urban planning. A map animation visualizing not only the extent of urban growth, but when and where sprawl occurs, can help the general public get an idea of how developing cities grow.

Data Collection

In-depth searches of online open data catalogues for vector based land use data cultivated little results. In the absence of detailed, well collected and precise land use data for Sào Paulo, I chose to analyze urban growth through the use of remote sensing. Imagery from Landsat satellites were collected, and further processed in PCI Geomatica and ArcGIS Pro for land use classification.

Data collection involved the use of open data repositories. In particular, free remotely sensed imagery from Landsat 4, 5, 7 and 8 can be publicly accessed through the United States Geological Survey Earth Explorer web page. This open data portal allows the public to collect imagery from a variety of satellite platforms, at varying data levels. As this project aims to view land use change over time, imagery was selected at data type level-1 for Landsat 4-5 Thematic Mapper and Landsat 8 OLI/TIRS. Imagery selected had to have at least less than 10% cloud cover, and had to be images taken during the daytime so that spectral values would remain consistent across each unsupervised image classification.

Landsat 4-5 imagery at 30m spectral resolution was used for the years between 2004 and 2010. Landsat-7 Imagery at 15m panchromatic resolution was excluded from search criteria, as in 2003 the scan-line corrector of Landsat-7 failed, making many of its images obsolete for precise land use analysis. Landsat 8 imagery was collected for the year 2014 and 2017. All images downloaded were done so at the Level-1 GeoTIFF Data Product level. In total, six images were collected for years 2004, 2006, 2007, 2008, 2010, 2014, 2017.

Data Processing

Imagery at the Level-1 GeoTIFF Data Product Level contains a .tif file for each image band produced by Landsat 4-5 and Landsat-8. In order to analyze land use, the image data must be processed as a single .tiff. PCI Geomatica remote sensing software was employed for this process. By using the File->Utility->Translate command within the software, the user can create a new image based on one of the image bands from the Landsat imagery.

For this project, I selected the first spectral band from Landsat 4-5 Thematic Mapper images, and then sequentially added bands 2,3,4,5, and band 7 to complete the final .tiff image for that year. Band 6 is skipped as it is the thermal band at 120m spatial resolution, and is not necessary for land use classification. This process was repeated for each landsat4-5 image.Similarly for the 2014 and 2017 Landsat-8 images, bands 2-7 were included in the same manner, and a combined image was produced for years 2014 and 2017.

Each combined raster image contained a lot of data, more than required to analyze the urban extent of Sào Paulo and as a result the full extent of each image was clipped. When doing your own map animation project, you may also wish to clip data to your study area as it is very common for raw imagery to contain sections of no data or clouds that you do not wish to analyze. Using the clipping/subsetting option found under tools in the main panel of PCI Geomatica Focus, you can clip any image to a subset of your choosing. For this project, I selected the coordinate type ‘lat/long’ extents and input data for my selected 3000×3000 pixel subset. The input coordinates for my project were: Upper left: 46d59’38.30″ W, Upper right: 23d02’44.98″ S, Lower right: 46d07’21.44″ W, Lower Left: 23d52’02.18″ S.

Land Use Classification

The 7 processed images were then imported into a new project in ArcPro. During importation, raster pyramids were created for each image in order to increase processing speeds. Within ArcPro, the Spatial Analyst extension was activated. The spatial analyst extension allows the user to perform analytical techniques such as unsupervised land use classification using iso-clusters. The unsupervised iso-clusters tool was used on each image layer as a raster input.

The tool generates a new raster that assigns all pixels with the same or similar spectral reluctance value a class. The number of classes is selected by the user. 20 classes were selected as the unsupervised output classes for each raster. It is important to note that the more classes selected, the more precise your classification results will be. After this output was generated for each image, the 20 spectral classes were narrowed down further into three simple land use classes. These classes were: vegetated land, urban land cover, and water. As the project primarily seeks to visualize urban growth, and not all types of varying land use, only three classes were necessary. Furthermore, it is often difficult to discern between agricultural land use and regular vegetated land cover, or industrial land use from residential land use, and so forth. Such precision is out of scope for this exercise.

The 20 classes were manually assigned, using the true colour .tiff image created from the image processing step as a reference. In cases where the spectral resolution was too low to precisely determine what land use class a spectral class belong to, google maps was earth imagery referenced. This process was repeated for each of the 7 images.

After the 20 classes were assigned, the reclassify tool under raster processing in ArcPro was used to aggregate all of the similar classes together. This outputs a final, reclassified raster with a gridcode attribute that assigns respective pixel values to a land use class. This step was repeated for each of the 7 images. With the reclassify tool, you can assign each of the output spectral classes to new classes that you define. For this project, the three classes were urban land use, vegetated land, and water.

Cartographic Element Choices:

It was at this point within ArcPro that I had decided to implement my cartographic design choices prior to creating my final map animation.

For each layer, urban land use given a different shade of red. The later the year, the darker and more opaque the colour of red. Saturation and light used in this manner helps assist the viewer to indicate where urban growth is occurring. The darker the shade of red, the more recent the growth of urban land use in the greater Sào Paulo region. In the final map animation, this will be visualized through the progression of colour as time moves on in the video.

ArcPro Map Animation:

Creating an animation in ArcPro is very simple. First, locate the animation tab through the ‘View’ panel in ArcPro, then select ‘Add animation’. Doing so will open a new window below your work space that will allow the user to insert keyframes. The animation tab contains plenty of options for creating your animation, such as the time frame between key frames, and effects such as transitions, text, and image overlays.

For the creation of my map animation, I started with zoomed-out view of South America in order to provide the viewer with some context for the study area, as the audience may not be very familiar with the geography of Sào Paulo. Then, using the pan tool, I zoomed into select areas of choice within my study area, ensuring to create new keyframes every so often such that the animation tool creates a fly-by effect. The end result explores the very same mapping extents as I viewed while navigating through my data.

While making your own map animation, ensure to play through your animation frequently in order to determine that the fly-by camera is navigating in the direction you want it to. The time between each keyframe can be adjusted in the animation panel, and effects such as text overlays can be added. Each time I activated another layer for display to show the growth of urban land use from year to year, I created a new keyframe and added a text overlay indicating to the user the date of the processed image.

Once you are satisfied with your results, you can export your final animation in a variety of formats, such as .avi, .mov, .gif and more. You can even select the type of resolution, or use a preset that automatically configures your video format for particular purposes. I chose the youtube export format for a final .mpeg4 file at 720p resolution.

I hope this blog was useful in creating your very own map animation on remotely sensed and classified raster data. Good luck!

Urban Development of San Francisco

By Hannah Burdett

SA8905 Geovisualization Project, Ryerson University

The Development of San Francisco

San Francisco is located in the center of Northern California. It started as a base for the gold rush of 1849, the city quickly became one of the most populated cities in the United States. Shortly thereafter, San Francisco was devastated by the 1906 earthquake. Development peaked in the 1900’s as San Francisco rebuilt areas demolished by the earthquake and fires to compensate the growing population. During the 1930’s the San Francisco-Oakland Bay Bridge and the Golden Gate Bridge were opened. Additionally, during World War II, San Francisco was a major mainland supply point and port of embarkation for the war in the Pacific. Both factors led to another peak in construction. After World War II, many American military personnel who had fallen in love with the city while leaving for or returning from the Pacific settled in the city. This led to promoting the development of the Sunset District, Visitacion Valley, and the total build-out of San Francisco. Starting in the latter half of the 1960’s, San Francisco became most recognized for the hippie movement. Currently, San Francisco has become known for finance and technology industries. There is a high demand for housing, driven by its close proximity to Silicon Valley, and a low supply of available housing has led to the city being one of America’s most expensive places to live.

Data

The data used for the time series animation was imported from data.gov. Data.gov is a repository for the US Governments open source data. The imported data included a Land use Shapefile for San Francisco. The shapefile included information such as land use, shape area, street address, street number, etc. The land use shapefile also included the year the building was built. The building years range from 1848 to 2016 displaying 153 years of urbanization. The buildings were represented as polygons throughout San Francisco. Additionally, a grey scale base map from ArcGIS Pro was displayed to create a more cohesive map design.

Time Series Animation

To develop the reconstruction of San Francisco throughout the years, both QGIS and ArcGIS Pro were utilized. Both platforms were used so to provide a comparison between time series animation tools from an open source application and a non-open source application.

QGIS is an open source geographic information systems application that provides data visualization, editing, and analysis through functions and plugins. To create the time series animation the Time Manager plugin was utilized. The Time Manager plugin animates vector features based on a time attribute. For this study the time attribute was the years built.

ArcGIS Pro is the latest professional desktop GIS from Esri. ArcGIS Pro enables users to view, explore, analyze, edit and share maps and data. Unlike QGIS, no additional plugins are required to create the animated time series.

QGIS Methodology

To generate the time series in QGIS, the land use shapefile was downloaded and opened in QGIS. The attribute table from the land use shapefile was then exported and opened in Excel so that the yrbuilt column could be reformatted to meet QGIS Time Manager requirements. The yrbuilt column had the data presented as YYYY format for building dates. QGIS Time Manager requires timestamps to be in YYYY-MM-DD. To correct the format, -01-01 was added to the end of each building year. The modified values were then saved into a new column called yrbuilt1. The Excel sheet was then imported into QGIS and joined to the land use shapefile.

In QGIS, each of the buildings was presented as polygons. The shapefile symbology was changed from single symbology to quantified symbology. In other words, the symbology for each of the polygons was broken down to seven classes defined by years. Each class was then distinguished by color, so that one may differentiate the oldest building from the newest buildings. Furthermore, a grey scale basemap was added to create a more cohesive map.

Furthermore, in the Time Manager settings, “Add Layer” was selected. The land use shapefile was chosen as the Layer of interest. The start time was set to the yrbuilt1 attribute, whereas the end time was set to “No end time – accumulate features”. This allows newer buildings to be added without older buildings being removed from the map. For the animation, each time frame will be shown for 100 milliseconds. The Time Manager plugin was then turned on so that the time series may run.

In order to export the time series animation, Time Manager offers an “Export Video” option. However, this exports the animation as an image series, not as an actual video. To correct this, the image series was uploaded to Mapbox where additional Mapbox styles were used to render the map. It was then exported as a Gif from Mapbox.

ArcGIS Pro Methodology

In ArcGIS Pro, the land use shapefile was imported. The symbology for each of the polygons was then broken down to seven classes defined by years. The same colours utilized in QGIS were applied to the classes in ArcGIS Pro to differentiate between the building years. Within the layer’s properties, the Layers Time was selected as “each feature has a single time field”. Furthermore, the start and end times were set to the newest and oldest building years. The number of steps were assigned a value of sixteen. In View, the animation was added, and the Time Slider Steps were imported. The time frames were set to match the QGIS animation so that both time series animations would run at the same speed. The time series animation was then exported as a Gif.

Final Animated Map

Finally, to create a cohesive animated map the exported Gif’s were complied together in PowerPoint. Additional map features, such as a legend, were designed within PowerPoint. A bar graph was added along the bottom of the map to show years of peak building construction. The final time series map was then exported as a .mp4 and upload to YouTube.

ArcPro Animation of 1923 Canoe Trip in Algonquin Park

By Sarah Medland

Geovis Course Project @RyersonGeo, SA8905, Fall 2018

Context

While searching the web for historic maps to inspire this project I came across the personal website of Bob and Diane McElroy. Their website includes an extensive personal collection of present and historic records of the natural environment within Ottawa Valley and Algonquin Park. The collection of thoughts and logs on their site consist of those of their ancestors – dating back many decades from now. The following map is a section of the one which was chosen for the purpose of this assignment. It dates back to 1921:

In July of 1923, a group of 4 men led by a guide embarked on a 12-day canoe-trip, creating a log of their route as they traveled. The map log included handwritten details by W. H. McConnell about wildlife, weather, and their experience in the Park.

Purpose:

to animate an artistic rendering of a historic canoeing route which…

– brings to life a historic map by integrating it with modern GIS technology

– reveals information from approx. a hundred years prior about an ever-popular canoeing area

Methods

To begin, the map was download as a JPEG and brought into ArcMap. A DMTI Spatial minor water bodies Shapefile was added. Using this present-day layer, labelled by lake name, it was fairly easy to align this with the lakes from the historic map. Some challenges arose as the map is from 1921 therefore its accuracy is questionable, however, I was able to geo-reference the map fairly well.

Historic Map in ArcMap where it was georeferenced to a present-day water bodies layer

Next, DEM tiles were downloaded from Scholar’s Geoportal. These were converted into a TIN using the raster to TIN tool in ArcMap, and then into TIN nodes using the TIN node tool. This allowed the tiles to be combined into one continuous TIN using the Create TIN tool which could be clipped to the extent of the map surface. Once the elevation surface was made, the map could be given height.

The map surface after it was draped over an elevated TIN surface and atmospheric effects were applied

To visualize the canoe route, a line Shapefile was created over the route drawn on the map. Campsites were also added as a point Shapefile which included a ‘Date’ field in the attribute table. In the ArcGIS Pro Global setting the map was draped over the TIN surface and campsites symbolized in 3D with the dates labelled.

An example of some of the original annotations on the map

Lastly, a animation following the canoe route was created in ArcGIS Pro. The animation was created to guide the viewer along the route of the 1923 trip and included annotations such as those above and historic pictures from the time period.

Results: The following video is the final product:

Telling a Story through a Time-series animation using Open Data

By: Brian Truong.

GeoVis Project @RyersonGEO SA8905, Fall 2018

Context

As a student and photographer, I have frequently walked around the streets of Toronto. I would often see homeless individuals in certain neighborhoods in Toronto. While at the time I was aware of some shelters across of Toronto, I never fully understood the Toronto shelter system as I thought organizations in Toronto were one and the same in terms of providing shelters to those who are at-risk. I also noticed that the City of Toronto updates their shelter occupancy data on a more less daily basis, which led me to choose this topic for my GeoViz project. My lack of knowledge of the shelter system and the readily available data, motivated me to choose to make a Time Series map along with incorporating ESRI’s Story Maps into the project. This was to ensure that whoever wanted to see my project could be told the story of Toronto Shelters as well.

Process

Toronto open data provides shelter occupancy data in multiple formations, however, a JSON data format was chosen due to previous experience with working with JSON data in Alteryx. JSON data was provided through a link from Toronto Open Data. Using Alteryx a scrip was created to download the live(ish) data, parse it, put it in a proper format, then filter the data, and along with creating appropriate columns to work with the data.

Above is an example of the JSON data that was used, the data itself is semi-structured as the data is organized in a specific format. The data consisted of multiple of entries for Shelter location, those were filtered out so that only organizational program was present for each shelter location. this usually went down too the program that housed the largest number of people. In order for a proper time series to be created, a date/time column must be present, columns were created through the use of the formula tool where columns such as date/time and occupancy rates were created.

Above is the final Alteryx strip that was used to get the data from a JSON format to a .xlsx format. However, there was one problem with the data. The data itself wasn’t geocoded, so I had to manually geocode each shelter location by running the address of each shelter through Google Maps and copy and pasting the (x and y) values of the shelter locations. These coordinates were then put into the same file as the output of the Alteryx script, except it was in a different sheet. Using VLOOKUP, shelters were assigned their coordinates through matching shelter names.

Time Series Map

The time series portion of this geoviz project was created using Arcmap Pro, the excel file was brought into ArcGIS Pro and points were created using x and y coordinates. A shapefile was created, in order to create a time series map, the time field had to be enabled. Below shows the steps needed to be taken in order to enable time as a field on a shapefile.

In order to actually enable time, a time column must already exist in the format of dd/mm/yyy XX:XX. From that point, the change in shelter occupancy could be viewed through a time-slider going at any interval that the user required. For this project, it went by a daily basis on a 3-minute loop. In order to capture it as a video and export it, the animation function was required. Within the animation tab, the tool append was used.

What the append feature does is that it follows the time series map from the first frame, which is on the first day of the time series map (Jan 1, 2018 00:00) to the last day of the time series map (Nov 11, 2018 00:00). The animation would then be created as per specifications of the settings. The video itself is exported through a 480p video at 15 frames a second. It was then uploaded on YouTube and embeded on the storymaps.

ESRI Story Maps

The decision to use ESRI’s story maps was in part due to what motivated me to work on this. I wanted to tell the story of shelters and who they serve and is affected by them. Especially after two major events in the past year that has led to shelters in Toronto showing up on the news. Both the cold snap in early 2018 and the large influx of migrants has had a huge effect on Toronto’s Shelters.

North American Impact Events throughout History – A Map Animation

By: Nicole Slattery. Geovis Project Assignment @RyersonGeo, SA8905, Fall 2018

For my Geovisualization assignment, I wanted to create an animated map of impact crater events in North America throughout history. I decided to use ArcGIS Pro in order to do this because of the nature of the data. The Earth Impact Database maintained by the Planetary and Space Science Centre (PSSC) in New Brunswick, has achieved the 190 confirmed impact craters from around the world. The impacts have occurred anywhere from 1850 million years ago to 600 000 years ago. Usually, when creating an animated map throughout time, the map software requires a date. The impacts did not occur within the span of the Gregorian calendar used today; therefore, this software cannot map this data. However, ArcGIS Pro includes a tool “Animate through a range” which allows for this data to be animated sequentially without a date.

2D Map of Impact Craters in North America

In order to utilize ArcGIS Pro’s animation through a range tool, the data points of impact craters were geocoded and added to a new map. The points were displayed by proportional symbols of their diameter on the earth in km. Therefore, the map displays the distribution of impact craters across North America by their diameter. The locations were symbolized as well, in a gradient colours brown to black, in order for the points to appear to have depth. The 2D map can be viewed above. The basemap of the map was added from the basemap gallery under the Map tab in ArcGIS Pro. The World Imagery basemap was selected; this layer presents high resolution satellite and aerial imagery of the world. Another interesting feature of ArcGIS Pro is that any 2D map can be converted to a 3D scene for data visualization. Under the View tab, the Convert button was selected. Within this drop-down menu, the option To a Global Scene was selected. This converted the map into a 3D globe.

Converting the 2D map into a Global Scene

Under Properties of the scene layer impact points, the range setting was enabled for the “Age” attribute of the layer. The age attribute describes when the impact occurred in MYA (millions of years ago). The range was set between 1850 and 0 MYA, as this is the full range of the data in the layer. A range slider was added to the side of the scene. By dragging the slider, the points animatedly appear and disappear depending on their ages.

Enabling Range on the “Age” Attribute of the Impacts

Range Slider (display at 1315 MYA)

In order to start an animation, the Add button was selected in the View tab. This created and opened an Animation tab within ArcGIS Pro. In order to start the video, the Range of visible data was selected as 1850-1850. This way only the oldest impact crater is displayed. The scene was zoomed out for the first shot of the animation. By setting the Append Time to 5 seconds and selecting Append, the first clip of animation was created. This clip was 5 seconds. In order to display the progression of impacts occurring, the slider was dragged closer throughout time. By increasing Append time to 15 seconds and selecting Append, the animation clip was created. The animation clip is range aware therefore it will progress through the range slider up to where the slider was dragged throughout this append time. This process was repeated until the whole range was animated.

Range set at 1850-1850 in order to start animation

After the range of ages of the impacts was animated, a camera path was animated in order to create an interesting visual. By zooming and changing the view of the map and using the append animation clip, a visualization of the satellite imagery of the impact craters was created. For example, the Sudbury crater was zoomed in upon and animated. Then, a paragraph of facts about the Sudbury crater was overlaid using the Overlay option in the Animation Tab. As well, a scale was overlaid using the same tool. This was done for three other craters and was added to the animation video.

Finally, the animation was exported as a MP4 file in order to easily share the file.

The Final Video seen above was uploaded to YouTube.